﻿////////////////////////////////////////////////////////////////////////////
//
// Copyright 2016 Realm Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
//
////////////////////////////////////////////////////////////////////////////

using System;
using System.Collections.Generic;
using System.Linq;
using System.Runtime.InteropServices;

namespace Realms.Sync.Native
{
    [StructLayout(LayoutKind.Sequential)]
    internal struct StringStringPair
    {
        internal static readonly int Size = Marshal.SizeOf<StringStringPair>();

        [MarshalAs(UnmanagedType.LPStr)]
        public string Key;

        [MarshalAs(UnmanagedType.LPStr)]
        public string Value;

        public static Dictionary<string, string> UnmarshalDictionary(IntPtr pairs, int pairsLength)
        {
            return Enumerable.Range(0, pairsLength)
                             .Select(i => Marshal.PtrToStructure<StringStringPair>(IntPtr.Add(pairs, i * StringStringPair.Size)))
                             .ToDictionary(pair => pair.Key, pair => pair.Value);
        }
    }
}